DESCRIPTION: (Investigator's Abstract) Infants treated in the Neonatal Intensive Care Unit (NICU) for preterm birth and/or perinatal complications are at risk for a variety of visual disorders, including reduced visual acuity, reduced visual field size, myopia, strabismus, and retinopathy of prematurity. The results of our current study have revealed that the infants at highest risk for visual disorders are those who had retinal abnormalities related to retinopathy of prematurity (ROP) or structural abnormalities of the brain, such as periventriculr leukomalacia (PVL), severe (grade III or IV) intraventricular hemorrhage (IVH), and structural abnormalities related to hypoxia/asphyxia of the full-term neonate (FHA). The goal of the proposed research is to continue to explore the relation between visual outcome and perinatal complications. Three research projects will be undertaken: 1) Continued Follow-Up of Infants Treated in the NICU. Grating acuity and visual field development between 24 and 48 months post-term age will be studied in 216 children whose visual development was assessed during the current grant period. Testing will indicate whether the perinatal complications that were associated with visual acuity or visual field deficits during infancy will also be associated with acuity and field deficits in early childhood. 2. Prospective Study of the Relation Between Brain Abnormalities and Visual Function. Development of grating acuity and visual fields will be measured in 70 infants with PVL, severe IVH, or FHA, in whom ultrasound (US), computed tomography (CT), and/or magnetic resonance imaging (MRI) scans of their brains are available. Comparison of structural and functional results in this population will indicate whether the wide variation in grating acuity and visual field development found in infants with PVL, severe IVH, or FHA is related to the location, severity, and extent of structural abnormalities present in the brains of these infants. 3. Validation and Improvement of Testing Techniques for Infants. Interobserver test-retest reliability and predictive validity of the acuity card procedure will be evaluated. In addition, an electronically-controlled kinetic perimeter will be developed, and the normative data that are required for the incorporation of the perimeter into clinical settings will be collected.